Millimeter wave radar

Abstract

The utility model provides a millimeter wave radar which is composed of a plurality of radar circuit boards, each radar circuit board is used for detecting the airspace of a preset range, and the detection range formed by combining all the radar circuit boards comprises an omnibearing angle. Therefore, the millimeter wave radar can realize omnibearing angle detection, does not need a motor and rotation, is simple in structure, is low in cost, is high in measurement precision, is good in stability, is high in practicality, and lays a reliable foundation for high-precision target measurement. The method has wide prospects in the application of automobile radars, obstacle avoidance radars, unmanned aerial vehicle radars, traffic radars and the like. The problems that in the prior art, cost is high, the electromagnetic environment is complex, and interference is likely to be formed on target detection are solved.

Description

Technical Field

[0001] The present application relates to the field of radar technology, and in particular to a millimeter wave radar. Background Art

[0002] Currently, the popular omnidirectional millimeter-wave radars on the market (i.e., radars that cover 360 degrees in the horizontal direction) mostly use rotating radars, which rotate the radar in the azimuth direction to detect targets and obstacles in all directions.

[0003] However, the structure of this solution is complex, involving detection target puzzles, high-computing FPGA (Field Programmable Gate Array), motors, wireless charging, WiFi data transmission, encoding boards, magnetic rings, AC power, etc. Therefore, the cost is relatively high, and the electromagnetic environment is complex, which is easy to interfere with the detection of the target. Utility Model Content

[0004] In view of this, the present application provides a millimeter wave radar to solve the problems in the prior art that the cost is relatively high, the electromagnetic environment is complex, and it is easy to interfere with the detection of the target.

[0005] To achieve the above objectives, this application provides the following technical solutions:

[0006] In a first aspect, the present application discloses a millimeter wave radar, which is composed of a plurality of radar circuit boards, each of which is used to detect an airspace within a preset range, and the detection range of all radar circuit boards combined includes all angles.

[0007] Optionally, the above-mentioned millimeter wave radar is composed of six radar circuit boards, and the detection range of each radar circuit board in the horizontal direction is greater than 60 degrees.

[0008] Optionally, the above-mentioned millimeter wave radar is composed of four radar circuit boards, and the detection range of each radar circuit board in the horizontal direction is greater than 90 degrees.

[0009] Optionally, the above-mentioned millimeter wave radar is composed of three radar circuit boards, and the detection range of each radar circuit board in the horizontal direction is greater than 120 degrees.

[0010] Optionally, in the above-mentioned millimeter wave radar, each radar circuit board is set to a synchronous working mode; wherein the synchronous working mode includes radio frequency synchronization and baseband synchronization.

[0011] Optionally, in the above-mentioned millimeter wave radar, each radar circuit board is set to a time-division working mode.

[0012] Optionally, in the above-mentioned millimeter-wave radar, only one radar circuit board is in working state in each working time period.

[0013] Optionally, in the above-mentioned millimeter-wave radar, during each working time period, a plurality of radar circuit boards are in a working state, wherein the radar circuit boards in the working state are not adjacent to each other.

[0014] Optionally, for the above-mentioned millimeter-wave radar, if the working mode of the millimeter-wave radar is the obstacle avoidance mode, each of the radar circuit boards operates independently and simultaneously and detects the target respectively. For the same target, the minimum value of the ranging, and / or the maximum value of the speed measurement, and / or the minimum value of the collision time are taken from the detection results of each of the radar circuit boards as the final detection result.

[0015] It can be seen from the above technical solution that the millimeter wave radar provided by the present application is composed of multiple radar circuit boards, each of which is used to detect the airspace within a preset range, and the detection range of all radar circuit boards combined includes all-round angles. It can be seen that the millimeter wave radar of the present application can realize all-round angle detection, does not require motors and rotation, and the radar has a simple structure, low cost, high measurement accuracy, good stability, and strong practicality, laying a reliable foundation for high-precision target measurement. It has broad prospects in the application of automotive radar, obstacle avoidance radar, drone radar, and traffic radar. It solves the problem that the cost of the prior art is relatively high, the electromagnetic environment is complex, and it is easy to interfere with the detection of the target. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0017] Figure 1 A schematic diagram of a millimeter wave radar structure disclosed in an embodiment of the present application;

[0018] Figure 2 An antenna layout diagram of a single radar circuit board disclosed in another embodiment of the present application;

[0019] Figure 3 The radiation pattern of the radar antenna disclosed in another embodiment of the present application at 25 GHz;

[0020] Figure 4 A curve showing the gain of a radar antenna varying with frequency according to another embodiment of the present application;

[0021] Figure 5This is a schematic diagram of another millimeter wave radar structure disclosed in another embodiment of the present application. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0023] In this application, the terms "comprises", "comprising" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.

[0024] Furthermore, in this document, relational terms such as first and second, etc. are used only to distinguish one entity or operation from another entity or operation, but do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0025] As can be seen from the background technology, most of the omnidirectional millimeter wave radars in the prior art use rotating radars, which rotate the radar in the azimuth direction, so that it is easy to detect targets and obstacles in all directions. Its structure is complex, involving detection target puzzles, high-computing FPGA, motors, wireless charging, WiFi data transmission, encoding boards, magnetic rings, alternating current, etc. Therefore, the cost is relatively high, and the electromagnetic environment is complex, which is easy to interfere with the detection of targets.

[0026] In view of this, the present application provides a millimeter wave radar to solve the problems in the prior art that the cost is relatively high, the electromagnetic environment is complex, and it is easy to interfere with the detection of the target.

[0027] The embodiment of the utility model provides a millimeter wave radar, which is composed of a plurality of radar circuit boards, each of which is used to detect an airspace within a preset range, and the detection range of all the radar circuit boards combined includes all angles.

[0028] It should be noted that the millimeter wave radar provided in this application is composed of multiple radar circuit boards, each of which is used to detect the airspace within a preset range, and the detection range of all radar circuit boards combined includes all angles. Among them, the specific number of radar circuit boards can be set according to actual needs. For example, six radar circuit boards are used. Figure 1 As shown in the figure, it is composed of six radar circuit boards. The detection range of each radar circuit board is 70 degrees. The detection range of all radar circuit boards combined can cover all angles, that is, 360 degrees in the horizontal direction. Among them, the antenna design of a single radar circuit board is as follows: Figure 2 The bottom one is the transmit (TX) antenna, and the top two are the receive (RX) antennas. Figure 3 is the radiation pattern of each antenna at 25GHz, where the Y-axis is the actual gain (dB), the X-axis is the azimuth (Theta), the dark solid line at the top is the gain curve at 25GHz and the elevation angle (Phi) is 0 degrees, the light solid line at the bottom is the gain curve at 25GHz and the elevation angle (Phi) is 90 degrees, and the 25 above represents 25GHz. Figure 1 It can be seen that the FOV of the antenna in the horizontal direction (i.e., the elevation direction of the antenna) is greater than 60 degrees (i.e., ±30 degrees), and the FOV in the vertical direction (i.e., the azimuth direction of the antenna) is greater than 100 degrees (i.e., ±50 degrees). In order to cover the full angle, i.e., 360 degrees in the horizontal direction, 6 radar circuit boards are required. Figure 4 It is a curve of the gain of each antenna changing with frequency, where the Y axis is the actual gain (dB), the X axis is the frequency (GHz), and the curve is the gain changing with frequency when the elevation angle (Phi) is 0 degrees and the azimuth angle is also 0 degrees. The center frequency of this antenna design is 25GHz, but by optimizing the size of the antenna, the center frequency of the antenna can be changed to 24.125GHz to effectively cover the commonly used 24GHz millimeter wave radar frequency band.

[0029] It should also be noted that the processing chip and circuit of the radar circuit board are on the other side of the radar circuit board, and the radio frequency is connected to the front antenna through a coaxial structure. This embodiment is a one-transmit-two-receive antenna arrangement. In practical applications, commonly used arrangements such as two-transmit-four-receive, or two-transmit-six-receive, or three-transmit-four-receive can also be used.

[0030] The millimeter wave radar provided by the present application is composed of multiple radar circuit boards, each of which is used to detect the airspace within a preset range, and the detection range of all radar circuit boards combined includes all-round angles. It can be seen that the millimeter wave radar of the present application can realize all-round angle detection, does not require motors and rotation, and the radar has a simple structure, low cost, high measurement accuracy, good stability, and strong practicality, laying a reliable foundation for high-precision target measurement. It has broad prospects in the application of automotive radar, obstacle avoidance radar, drone radar, and traffic radar. It solves the problem that the cost of the prior art is relatively high, the electromagnetic environment is complex, and it is easy to interfere with the detection of the target.

[0031] Optionally, in another embodiment of the present application, the above-mentioned millimeter wave radar is composed of six radar circuit boards, and the detection range of each radar circuit board in the horizontal direction is greater than 60 degrees.

[0032] Optionally, in another embodiment of the present application, the millimeter wave radar is composed of four radar circuit boards, each of which has a detection range greater than 90 degrees in the horizontal direction. Figure 5 At this time, the horizontal direction of each radar circuit board must cover more than 90 degrees, so that it can cover the full angle of 360 degrees.

[0033] Optionally, in another embodiment of the present application, the above-mentioned millimeter wave radar is composed of three radar circuit boards, and each radar circuit board has a detection range greater than 120 degrees in the horizontal direction, so as to cover an all-round angle of 360 degrees.

[0034] Optionally, in another embodiment of the present application, the above-mentioned millimeter-wave radar is composed of three radar circuit boards, and each radar circuit board has a detection range greater than 90 degrees in the horizontal direction; wherein the millimeter-wave radar is used to detect the front and the left and right sides.

[0035] It should be noted that in some scenarios, such as when a drone is flying, it only cares about targets and obstacles in front and on the left and right sides, but not targets and obstacles in the rear. Therefore, three radar circuit boards with a horizontal detection range greater than 90 degrees are combined to form a millimeter-wave radar for detecting the front and left and right sides.

[0036] Optionally, in another embodiment of the present application, the above-mentioned millimeter-wave radar is composed of five radar circuit boards, and each radar circuit board has a detection range greater than 50 degrees in the horizontal direction; wherein the millimeter-wave radar is used to detect the front and the left and right sides.

[0037] Optionally, in another embodiment of the present application, each of the radar circuit boards is set to a synchronous working mode; wherein the synchronous working mode includes radio frequency synchronization and baseband synchronization.

[0038] It should be noted that, taking six radar circuit boards as an example, these six radar circuit boards can work in a simultaneous transmission mode, and in this case, the six radar circuit boards need to be synchronized in RF. For 24GHz radars, RF cables can be used to synchronize the RF of the six radar circuit boards. One of the radar circuit boards is used as the main board, and the other five radar circuit boards are used as slave boards. The main board generates a 24GHz RF synchronization signal, which reaches the main board and the slave board through the same length of RF path, so that the RF of the six radar circuit boards is synchronized. In this case, the six radar circuit boards can detect at the same time. For 77GHz millimeter-wave radars, their RF synchronization signal is also 24GHz, and their chip can use the AWR2243 chip. At the same time, there is baseband synchronization, that is, the synchronization signals of some other clocks and crystal oscillators, which also need to be connected synchronously.

[0039] Or, taking four radar circuit boards as an example, these four radar circuit boards can work in a simultaneous transmission mode, in which case the four radar circuit boards need to be synchronized in RF. For 24GHz radars, RF cables can be used to synchronize the RF of the four radar circuit boards. One of the radar circuit boards is used as the main board, and the other three radar circuit boards are used as slave boards. The main board generates a 24GHz RF synchronization signal, which reaches the main board and the slave board through the same length of RF path, so that the RF of the four radar circuit boards is synchronized. In this case, the four radar circuit boards can detect targets and obstacles at the same time. Of course, there are other baseband signals that need to be synchronized, such as clock and crystal oscillator signals.

[0040] Optionally, in another embodiment of the present application, each of the radar circuit boards is set to a time-division working mode.

[0041] In each working time period, only one of the radar circuit boards is in working state.

[0042] Alternatively, in each working time period, a plurality of radar circuit boards are in working state, wherein the radar circuit boards in working state are not adjacent to each other.

[0043] It should be noted that, taking six radar circuit boards as an example, these six radar circuit boards can also work in sequence in a time-division manner, so that RF synchronization and baseband synchronization are not required. If these radar circuit boards are numbered 1, 2, 3, 4, 5, and 6 in sequence, there are the following time-division methods:

[0044] First, only one radar circuit board works in each time period. For example, when board 1 works, other radar circuit boards do not work.

[0045] Second, only two radar circuit boards work in each time period, and these two radar circuit boards are back-to-back. For example, when board 1 works, board 4 also works, and other radar circuit boards do not work. When boards 2 and 5 work, other boards do not work. When boards 3 and 6 work, other boards do not work. In this way, since the antennas are back-to-back, there is little interference between each other, and the speed of scanning a circle can be accelerated.

[0046] Third, only three radar circuit boards work in each time period, and these three radar circuit boards are separated from each other. For example, when board 1 works, boards 3 and 5 also work, and other radar circuit boards do not work. When boards 2, 4, and 6 work, other boards do not work. In this way, when one antenna transmits, the two adjacent antennas do not transmit, thus reducing mutual interference and making the scanning speed faster.

[0047] It can be seen from the above that under these time division modes, the antennas of the radar circuit boards working simultaneously have a certain degree of spatial isolation, that is, space division, which can reduce mutual interference between antennas.

[0048] Alternatively, taking four radar circuit boards as an example, these four radar circuit boards can also work in sequence in a time-division manner, so that RF synchronization and baseband synchronization are not required. If these radar circuit boards are numbered 1, 2, 3, and 4 in sequence, there are the following time-division methods:

[0049] First, only one radar circuit board works in each time period. For example, when board 1 works, other radar circuit boards do not work.

[0050] Second, only two radar circuit boards work in each time period, and these two radar circuit boards are back-to-back. For example, when board 1 works, board 3 also works, and other radar circuit boards do not work. When boards 2 and 4 work, other boards do not work. In this way, since the antennas are back-to-back, there is little interference between each other, and the speed of scanning a circle can be accelerated.

[0051] Optionally, in another embodiment of the present application, if the working mode of the millimeter-wave radar is the obstacle avoidance mode, each of the radar circuit boards operates independently and detects the target separately. For the same target, the minimum value of the ranging, and / or the maximum value of the speed measurement, and / or the minimum value of the collision time are taken from the detection results of each of the radar circuit boards as the final detection result.

[0052] It should be noted that if the millimeter wave radar described above is used for obstacle avoidance, then the various radar circuit boards do not need to be synchronized. Each of the radar circuit boards operates independently and detects targets separately. For the same target, the minimum value of the distance measurement, and / or the maximum value of the speed measurement, and / or the minimum value of the collision time are taken as the final detection result from the detection results of each of the radar circuit boards. For example, for the same target, the distance measured by circuit board No. 1 is 10 meters, the speed is 15m / s, and the collision time is 3s; and for the same target, the distance measured by circuit board No. 2 is 9 meters, the speed is 12m / s, and the collision time is 2s; then the safest principle is adopted when avoiding obstacles, and the target distance of 9 meters, and / or the speed of 15m / s, and / or the collision time of 2s are taken as the final detection result. In this way, there is no need for cumbersome synchronization design, and it can be used accurately for obstacle avoidance.

[0053] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can refer to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system or system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiment. The system and system embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without creative work.

[0054] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present utility model.

[0055] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A millimeter wave radar, characterized in that: It is composed of multiple radar circuit boards, each of which is used to detect airspace within a preset range. The detection range of all radar circuit boards combined includes all angles.

2. The millimeter wave radar according to claim 1, characterized in that: It is composed of six radar circuit boards, and each radar circuit board has a detection range greater than 60 degrees in the horizontal direction.

3. The millimeter wave radar according to claim 1, characterized in that: It is composed of four radar circuit boards, and each radar circuit board has a detection range greater than 90 degrees in the horizontal direction.

4. The millimeter wave radar according to claim 1, characterized in that: It is composed of three radar circuit boards, and each radar circuit board has a detection range greater than 120 degrees in the horizontal direction.

5. The millimeter wave radar according to claim 1, characterized in that: It is composed of three radar circuit boards, each of which has a detection range greater than 90 degrees in the horizontal direction; wherein the millimeter wave radar is used to detect the front and the left and right sides.

6. The millimeter wave radar according to any one of claims 1 to 5, characterized in that: Each of the radar circuit boards is set to a synchronous working mode; wherein the synchronous working mode includes radio frequency synchronization and baseband synchronization.

7. The millimeter wave radar according to any one of claims 1 to 5, characterized in that: Each of the radar circuit boards is set to a time-division working mode.

8. The millimeter wave radar according to claim 7, characterized in that: In each working time period, only one of the radar circuit boards is in working state.

9. The millimeter wave radar according to claim 7, characterized in that: In each working time period, a plurality of radar circuit boards are in working state, wherein the radar circuit boards in working state are not adjacent to each other.

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